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$ httpd -lThe module mod_so should be part of the displayed list. If these requirements are fulfilled you can easily extend your Apache server's functionality by installing your own modules with the DSO mechanism by the help of this apxs tool:
$ apxs -i -a -c mod_foo.c gcc -fpic -DSHARED_MODULE -I/path/to/apache/include -c mod_foo.c ld -Bshareable -o mod_foo.so mod_foo.o cp mod_foo.so /path/to/apache/modules/mod_foo.so chmod 755 /path/to/apache/modules/mod_foo.so [activating module `foo' in /path/to/apache/etc/httpd.conf] $ apachectl restart /path/to/apache/sbin/apachectl restart: httpd not running, trying to start [Tue Mar 31 11:27:55 1998] [debug] mod_so.c(303): loaded module foo_module /path/to/apache/sbin/apachectl restart: httpd started $ _The arguments files can be any C source file (.c), a object file (.o) or even a library archive (.a). The apxs tool automatically recognizes these extensions and automtaically used the C source files for compilation while just using the object and archive files for the linking phase. But when using such pre-compiled objects make sure they are compiled for position independend code (PIC) to be able to use them for a dynamically loaded shared object. For instance with GCC you always just have to use -fpic . For other C compilers consult its manual page or at watch for the flags apxs uses to compile the object files. For more details about DSO support in Apache read the documentation of mod_so or perhaps even read the src/modules/standard/mod_so.c source file.
12 -n " modname" This explicitly sets the module name for the -i (install) and -g (template generation) option. Use this to explicitly specify the module name. For option -g this is required, for option -i the apxs tool tries to determine the name from the source or (as a fallback) at least by guessing it from the filename.
Query options:
12 -q Performs a query for apxs 's knowledge about certain settings. The query parameters can be one or more of the following strings:
CC TARGET CFLAGS SBINDIR CFLAGS_SHLIB INCLUDEDIR LD_SHLIB LIBEXECDIR LDFLAGS_SHLIB SYSCONFDIR LIBS_SHLIBUse this for manually determining settings. For instance use
INC=-I`apxs -q INCLUDEDIR`inside your own Makefiles if you need manual access to Apache's C header files.
Configuration options:
12 -S " name=value" This option changes the apxs settings described above.
Template Generation options:
12 -g This generates a subdirectory name (see option -n ")" and there two files: A sample module source file named mod_ name.c which can be used as a template for creating your own modules or as a quick start for playing with the APXS mechanism. And a corresponding Makefile for even easier build and installing of this module.
DSO compilation options:
12 -c This indicates the compilation operation. It first compiles the C source files (.c) of files into corresponding object files (.o) and then builds a dynamically shared object in dsofile by linking these object files plus the remaining object files (.o and .a) of files If no -o option is specified the output file is guessed from the first filename in files and thus usually defaults to mod_ name.so
12 -o " dsofile" Explicitly specifies the filename of the created dynamically shared object. If not specified and the name cannot be guessed from the files list, the fallback name mod_unknown.so is used.
12 -D " name=value" This option is directly passed through to the compilation command(s). Use this to add your own defines to the build process.
12 -I " incdir" This option is directly passed through to the compilation command(s). Use this to add your own include directories to search to the build process.
12 -L " libdir" This option is directly passed through to the linker command. Use this to add your own library directories to search to the build process.
12 -l " libname" This option is directly passed through to the linker command. Use this to add your own libraries to search to the build process.
12 -Wc, "compiler-flags" This option passes compiler-flags as additional flags to the compiler command. Use this to add local compiler-specific options.
12 -Wl, "linker-flags" This option passes linker-flags as additional flags to the linker command. Use this to add local linker-specific options.
DSO installation and configuration options:
12 -i This indicates the installation operation and installs one or more dynamically shared objects into the server's modules directory.
12 -a This activates the module by automatically adding a corresponding LoadModule line to Apache's httpd.conf configuration file, or by enabling it if it already exists.
12 -A Same as option -a but the created LoadModule directive is prefixed with a hash sign (#), i.e. the module is just prepared for later activation but initially disabled.
12 -e This indicates the editing operation, which can be used with the -a and -A options similarly to the -i operation to edit Apache's httpd.conf configuration file without attempting to install the module.
$ apxs -c mod_foo.c gcc -fpic -DSHARED_MODULE -I/path/to/apache/include -c mod_foo.c ld -Bshareable -o mod_foo.so mod_foo.o $ _Then you have to update the Apache configuration by making sure a LoadModule directive is present to load this shared object. To simplify this step apxs provides an automatic way to install the shared object in its "modules" directory and updating the httpd.conf file accordingly. This can be achieved by running:
$ apxs -i -a mod_foo.c cp mod_foo.so /path/to/apache/modules/mod_foo.so chmod 755 /path/to/apache/modules/mod_foo.so [activating module `foo' in /path/to/apache/etc/httpd.conf] $ _This way a line named
LoadModule foo_module modules/mod_foo.sois added to the configuration file if still not present. If you want to have this this disabled per default use the -A option, i.e.
$ apxs -i -A mod_foo.cFor a quick test of the APXS mechanism you can create a sample Apache module template plus a corresponding Makefile via:
$ apxs -g -n foo Creating [DIR] foo Creating [FILE] foo/Makefile Creating [FILE] foo/mod_foo.c $ _Then you can immediately compile this sample module into a shared object and load it into the Apache server:
$ cd foo $ make all reload apxs -c mod_foo.c gcc -fpic -DSHARED_MODULE -I/path/to/apache/include -c mod_foo.c ld -Bshareable -o mod_foo.so mod_foo.o apxs -i -a -n "foo" mod_foo.so cp mod_foo.so /path/to/apache/modules/mod_foo.so chmod 755 /path/to/apache/modules/mod_foo.so [activating module `foo' in /path/to/apache/etc/httpd.conf] apachectl restart /path/to/apache/sbin/apachectl restart: httpd not running, trying to start [Tue Mar 31 11:27:55 1998] [debug] mod_so.c(303): loaded module foo_module /path/to/apache/sbin/apachectl restart: httpd started $ _You can even use apxs to compile complex modules outside the Apache source tree, like PHP3:
$ cd php3 $ ./configure --with-shared-apache=../apache-1.3 $ apxs -c -o libphp3.so mod_php3.c libmodphp3-so.a gcc -fpic -DSHARED_MODULE -I/tmp/apache/include -c mod_php3.c ld -Bshareable -o libphp3.so mod_php3.o libmodphp3-so.a $ _because apxs automatically recognized C source files and object files. Only C source files are compiled while remaining object files are used for the linking phase.